Started Using Video to Improve my Serve

I started hitting balls with my wife regularly for the last month. Been taking advantage of the opportunity to get serve reps have her record a few of my serves. I've found it really helps me get the kinks out and shows me what to work on.

My serve had regressed due to lack of practice and is currently the weakest part of my game (5.0 player right now). But 10 years ago (and even moreso, 20 years ago), my serve was my big weapon. I've improved my serve form in the last few weeks, but still a long way to go to get back to the hammer of my tournament days.

Here's a hard slider followed by a hard topspin second. I hope to post an improvement soon - my goal is to hit the curtain >7 ft high (been 10 years since I could last do that consistently).

Thanks for the vid! Can see how this was a weapon - it has some decent heat/racket head speed, and once you brush off the cobwebs youll be flying again in no time I reckon.

Are you conciously trying to jump when you serve? It just seems that a lot of your leg drive is being used to get you to jump up vertically and not into the court at all. There is only a limited amount of forward momentum and you seem to go up and down on the spot a bit. This might be inhibiting your serve speed.

My old serve used have much more jump. I used to land further in the court than anybody - about 6 feet in (and higher too). My jump serve was a little like Battistone, but without the extra step. Today I seemed to land about 1-2 feet in. I'm working toward getting more forward jump back in general, as that used to be my secret (in spite of the fact that few pros do it). But today I was testing out a ball toss location a little less out in front, and it seems to have led to less forward jump (I'm usually at 2-3 feet these days). Mostly, I use the height that my ball hits the curtain to guide my tweaks.

Other things I'm working on are:
1. Getting my hips further out in front of my shoulders in the trophy position.
2. Turning my back to the net more in the trophy position.
3. Finding the optimum toss location.
4. Raising my contact point higher (might need to jump higher to do this).
5. Pulling the racquet down faster to have more distance to accelerate the racquet upward.
6. Experimenting with wider stance with rear foot further back for better weight transfer (like I used to).

I think you loose energy from the ground up. It's visible when you look at your right leg. It comes around your body and it is not travelling backwards. If you take a look at this you'll see that his right leg points backwards. I believe that is due to Roddick activating his glutes for hip rotation. If you fire your glutes more, I think the leg kick back automatically and you will have a power increase (that is if your timing has adjusted)

The impact parts of the serve are too fast for standard frame rate video cameras. At 30 fps, a frame is taken every 33 milliseconds (0.033 second); at 60 fps, a frame is taken every 17 milliseconds (0.017 second).

The racket goes from the edge on to the ball to ball impact in about 20 milliseconds. Likely, at 30 fps for this 20 milliseconds you would get only one or no frames and with 60 fps one or two frames. The very rapid internal shoulder rotation can be seen by the rotation of the elbow bones & upper arm - more apparent later in the video, after ball impact.

This video & its thumnail from behind show the critical angle between the arm and racket at impact. This rapidly changing angle is visible for only a few milliseconds around impact as the racket is moving very fast.

From the side view, most people looking at serve videos don't notice that the racket is at an angle to the arm at impact.

You don't have a high speed video camera? Check, because a lot of cameras have high speed video modes such as the Canon Powershot cameras.

Some compromise tricks to get the most information from your video camera:

1) Always shoot in direct sunlight (sharp shadows are cast) because the light levels are roughly 100X those of indoor tennis courts. Your video camera most probably uses automatic exposure control and it will usually adjust exposure by using faster shutter speeds for high light levels. Result - the video will have much less motion blur and you might be able to accurately see where the arm, racket, ball, etc are located. Most smartphones use very fast shutter speeds in direct sunlight so that the images of fast moving objects are very sharp.

2) Some new DSLR's have manual exposure control or shutter priority (auto) shutter speed adjustments for video. Some offer very fast shutter speeds such as 1/4000 second. These cameras might also have 60 fps.

3) View from high & directly behind the server so that the camera views along the ball's trajectory. That is both an informative view and since the racket is moving away from the camera at impact the motion blur will be greatly reduced at the time of impact- lower motion blur.

4) For 30 or 60 fps cameras, repeat the same serve until you catch one where you can see ball impact as shown in the above video thumbnail.

5) Consider any Jello Effect distortions produced in video cameras of very rapidly moving objects, especially so with high resolution HD smartphone cameras.

You can get a lot of information, mostly for the slower body parts, from your current videos. But the motion blur and low frame rate will always obscure the fastest parts of the serve, especially those in the last 0.05 second leading to ball impact. It could be very misleading to develop your serve based on videos that can't show what is happening at impact.

Nobody can ever bounce a serve 7' high at the backboard. Not Isner, not Dr.Ivo, not Battisone, not any of us.
Hot weather, abrasive court, TALL guy, maybe 4-5' up the backboard.
Now you can hit a rock or something on a court and do it, but that's not really a consistent bounce, is it?
Nice motion, you're getting old, lost some pop and some lift.

LeeD. Yes you can hit it 7' or more up the back fence. It has to be a big serve with a lot of topspin. The spin is more important than the velocity. A flat serve can't do it, it will only hit the back fence harder, not much higher past a certain velocity.

Nobody can ever bounce a serve 7' high at the backboard. Not Isner, not Dr.Ivo, not Battisone, not any of us.
Hot weather, abrasive court, TALL guy, maybe 4-5' up the backboard.
Now you can hit a rock or something on a court and do it, but that's not really a consistent bounce, is it?
Nice motion, you're getting old, lost some pop and some lift.

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You so sure about that Lee?

I was at Indian Wells watching a match against the back fence (seating) right above the middle line judge. Balls hit by Karlovic were almost getting us.:shock:

I can't say with certainty but I'd reckon that some would be hitting 7' up on a regular court fence.

good pace.
i'm going with 'not efficient' though.
you're losing a lot of energy with the jump and you're also hitting while your body is falling.
you have a live arm and you are using your legs but timing is off. (not hitting on the way up) (check out essentialtennis.com's free serve course in 3 parts for good info on that)

i'm going to guess you hit a lot of serves long, right?
you need to incorporate some hip coiling. you have none currently. minus a minimum of 5mph right there.
could use some more cartwheel too.
I'd bet with that live arm and a little better timing, coil and some more cartwheel you could hit at least 10mph faster which is a lot.
Also, that first serve is not a slice.

ays.
Here's a hard slider followed by a hard topspin second. I hope to post an improvement soon - my goal is to hit the curtain >7 ft high (been 10 years since I could last do that consistently).http://youtu.be/cKfoTV9GquM

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If those courts are the ones I think they are (the ones whose mascot is
the smaller version of the Malamute) , I might be visiting there
in early July. Want to meet up for some tennis then?

Big difference between what you can do now, compared to what you think you used to do.
You're not even all that old.

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I'm 40. You don't have to remind me that I'm over the hill. But how do you know that I'm not baiting you in? Why would I post a video showing a 2nd serve hitting less than 5' high on the fence, then publicly challenge myself to go 2 feet higher, unless I was confident that I can go significantly higher?

Yes, the form in my video has some biomechanical flaws and is not up to the level up my biggest serves of the past - I don't jump forward nearly as far into the court as I used to, for starters. However, even if my form remains the same as in the video, I can still pick up quite a boost in bounce height simply by changing a few things:

1. The serves in the video were with half-dead balls. New balls ought to add a foot, right?
2. The serves in the video were were with kevlar hybrid strung tight in a dense pattern. Switching to an extended OS with open pattern, strung loose with syn gut might add another?
3. I use a racquet with 370 SW. In my experience, serve speed with a heavy racquet can improve rapidly with more reps because my arm strength improves rapidly when I am able to hit serves several times a week instead of once every 2 weeks. I just starting serving 2x per week a few weeks ago, so I can still gain here if I can continue to get serve reps over the summer.

My old serve used have much more jump. I used to land further in the court than anybody - about 6 feet in (and higher too). My jump serve was a little like Battistone, but without the extra step. Today I seemed to land about 1-2 feet in. I'm working toward getting more forward jump back in general, as that used to be my secret (in spite of the fact that few pros do it). But today I was testing out a ball toss location a little less out in front, and it seems to have led to less forward jump (I'm usually at 2-3 feet these days). Mostly, I use the height that my ball hits the curtain to guide my tweaks.

Other things I'm working on are:
1. Getting my hips further out in front of my shoulders in the trophy position.
2. Turning my back to the net more in the trophy position.
3. Finding the optimum toss location.
4. Raising my contact point higher (might need to jump higher to do this).
5. Pulling the racquet down faster to have more distance to accelerate the racquet upward.
6. Experimenting with wider stance with rear foot further back for better weight transfer (like I used to).

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I have not doubt your serve will get faster, with #1 being your biggest source of added power.
[It will also solve your swinging your right leg around as the greater force exerted upward/forward will overcome your currently stronger coil/uncoil force.]

You may also be able to tweak keeping your tossing arm up straighter and a little longer to get better shoulder over shoulder action.

The racquet drop should be "passive", with the added distance down a function of the leg push off so fast it leaves your racquet/arm behind. Is there possibly a little more juice left in the legs?

A bigger racquet supination at the racquet drop also should be "passive" based on the rapid uncoiling swinging that racquet well over to the left with a "limp" wrist.

Your practicing more will be your biggest ticket to success.

Having perfect timing in the kinetic chain elements to build on them in succession will put you over the top.

With that in mind, you may consider trying a slightly lighter frame to get more reps in.

Over time, reconsider whether a tiny more bit of pace on your 5 foot kicker is more productive in match play that a 7 foot kick - I'm sure you have seen many 5.0's will just move in to take it on the rise. (Still, the more options the better.)

Just listen to your body - it would be a pity to suffer an injury when you love tennis so much and already have a serve most would love to have.

OP, solid serve. I have never really looked at how high my serves bounce, but you have me intrigued.

The only advice I would give is that you seem to be jumping straight up and then swinging instead of jumping into the serve (if that makes sense). It seems like you are losing power right before impact because you are coming back down.

I have not doubt your serve will get faster, with #1 being your biggest source of added power.
[It will also solve your swinging your right leg around as the greater force exerted upward/forward will overcome your currently stronger coil/uncoil force.]

You may also be able to tweak keeping your tossing arm up straighter and a little longer to get better shoulder over shoulder action.

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Thanks - I forgot to mention toss reliability as something I need to work on.

The racquet drop should be "passive", with the added distance down a function of the leg push off so fast it leaves your racquet/arm behind.

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I actually disagree with this one. I think pulling the racquet down faster (instead of relying on gravity, was one of the secret sources of racquetspeed that I discovered 10 years ago when I was serving at a much higher level). By actively pulling the racquet down, I can get the bottom of the downswing much lower (down around my thigh rather than my waist). This gives me more distance to accelerate upward into the ball. It allows me to use the muscle chain in my abdominals, lat, shoulder, and triceps as a spring -- so in that sense I get extra energy into the racquet on the upstroke. I notice this is also one of Roddick's secrets, but very few amateurs do it. It gives the appearance of a "live arm", but really, my arm is not very live at all - I can't though a baseball particularly fast, but I can serve at a high level when my biomechanics click.

I'm wondering this - last night, I tried testing how far out into the court I could land, and it was depressing - I had trouble landing further than 4 feet in. It was like my leg push had evolved toward an old-man style serve, and I'd forgotten how to push off like I used to. I definitely have some work to do in this area. I also experimented last night with a pinpoint style -- it did let me get my hips a little further out in into the court, but it threw off my timing, so I'm not sure I want to go that direction.

With that in mind, you may consider trying a slightly lighter frame to get more reps in.

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I disagree here. After a few weeks of serving reps, my "Samprasized" Blade is startign to feel like an extension of my arm. There's also no question that I can serve faster and with significantly more rpm with 370 SW than I can with a stock racquet.

Over time, reconsider whether a tiny more bit of pace on your 5 foot kicker is more productive in match play that a 7 foot kick - I'm sure you have seen many 5.0's will just move in to take it on the rise. (Still, the more options the better.)

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Agree. Even if I never get to the elusive 7 ft mark, the extra reps will definitely make my serve more of a weapon, with more pop available to use for a variety of serve types.

Just listen to your body - it would be a pity to suffer an injury when you love tennis so much and already have a serve most would love to have.

Good luck!

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I've reached the age where I feel like running full sprint to reach a drop shot is a risky proposition - the speed is still there, but the chance of tweaking an achilles, my knee, or my hammy means sometimes the smart move is to let it go.

I actually disagree with this one. I think pulling the racquet down faster (instead of relying on gravity, was one of the secret sources of racquetspeed that I discovered 10 years ago when I was serving at a much higher level). By actively pulling the racquet down, I can get the bottom of the downswing much lower (down around my thigh rather than my waist). This gives me more distance to accelerate upward into the ball. It allows me to use the muscle chain in my abdominals, lat, shoulder, and triceps as a spring -- so in that sense I get extra energy into the racquet on the upstroke. I notice this is also one of Roddick's secrets, but very few amateurs do it. It gives the appearance of a "live arm", but really, my arm is not very live at all - I can't though a baseball particularly fast, but I can serve at a high level when my biomechanics click.

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It's interesting that you are using an active pulling down of your racquet.
I was quoting the analysis of Brian Gordon from his articles on the service technique on tennisplayer.net based on analysis of D1 college players and pros. He specifically cites the rapid racquet drop of Roddick and has a video clip of him in this section, and mentions how he has perfect timing of his leg drive.

Unfortunately as we get older the leg drive diminishes and so maybe you have found a way to get a quicker/fuller racquet drop with an active muscular contraction.

But Brian warns that an active contraction to get a deeper racquet drop, followed by an active contraction to get the racquet coming up can be too violent a reversal of forces, and can lead to shoulder injury.
Hopefully your method is "just right".

I disagree here. After a few weeks of serving reps, my "Samprasized" Blade is startign to feel like an extension of my arm. There's also no question that I can serve faster and with significantly more rpm with 370 SW than I can with a stock racquet.

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That's great that you can get in the reps with your weighted racquet. It sounds like you are getting close to the motion you want anyway.
I play/serve less over the winter, and in the spring need a lot of practice reps before the timing is right of the entire kinetic chain. It occurred to me I could use an unleaded 6.1 90 while initially warming up, and save my weighted stick until I was getting close. It sounds like you are already long past this point.

I don't see a way to contact you via your TW profile, but you can reach my
via my TW profile.

Coincidentally, I also used to toss pretty far into the court. I started doing
it because I was a serve and volleyer and it helped me get to the net
quicker. As a side benefit, it also helped me hit my serve harder.
I think I landed about 4 feet inside the court. Fast forward to today and
I don't toss deep in the court anymore, don't serve and volley, or serve
as hard, but your thread has me thinking that maybe I should start trying
to toss deep in the court again. I had a pinpoint stance. Now it's platform.

How would you describe your game? Were you a S&V player back in your heyday?

Also, if it is any consolation, I am right there with you in the land-bound white man category.

In doubles matches when my partner serves and I have to hit an overhead off of a lob return I usually get a standing ovation if I can get far enough off the ground for a credit card laid flat to be slid under my feet.

You have motivated me to go video my serve since it has been a while, and I am curious if there is a difference between my normal frame in MPH and my prestige codenamed SGO.

Oftentimes, a toss forward can shorten reply time, but not hit faster or make the ball bounce higher.
Can we agree a backspin serve bounces lower than a topspin serve?
Tossing too far forwards often encourages a backspin serve when trying to hit really hard.
Tossing just in front of the baseline can often account for a serve that his hit with a slight forward spin, not a topspin serve per se, but a flat serve with a dead ball effect. Those seem to go the fastest and really bounce high.
I know this is counter to what lots of you have noticed, but I've talked to guys with big serves, and they all say that going to net often compromises their bounce and pace.

How would you describe your game? Were you a S&V player back in your heyday?

Also, if it is any consolation, I am right there with you in the land-bound white man category.

In doubles matches when my partner serves and I have to hit an overhead off of a lob return I usually get a standing ovation if I can get far enough off the ground for a credit card laid flat to be slid under my feet.

You have motivated me to go video my serve since it has been a while, and I am curious if there is a difference between my normal frame in MPH and my prestige codenamed SGO.

J

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Might as well tell my tennis history here. My style of play has evolved through the years, with several distinct eras:

Phase I - The formative years:

I started late. I took a few group lessons when I was 12, then broke my arm, and didn’t play much until I was a 14-yr-old 9th grader trying out for the high school team.

I was pretty athletic, but my tennis skills were raw – in junior high, my 4x100m relay team won the WA state championship at the Hershey meet, and second place was 40m back. And I could dunk a volley ball by the time I started high school (hands too small to palm a basketball). I also had the second fastest time in the district at the 75m hurdles in junior high (the guy with the fastest time was Donnie Marshall, who went on to have an NBA career). Won a handful of blue ribbons in the high jump (even though my form sucked), and broke 19 ft to letter in the long jump my sophomore year. I gave up track and field to focus on tennis after 10th grade when I realized I was the only white guy in the starting blocks, and I wasn’t winning races anymore.

My tennis game in high school was all based on utilizing my physical advantages over my opponent. I was 5’11”, 155 lbs (about the same size I am now). But I always had a speed and quickness advantage against 99% of the players I faced. My 2hb was solid and reliable, but my fh was god-awful. I could find a way to loop or shovel it over the net if I had to (often with a moonball). On the forehand return, I was better blocking it back with a volley stroke.

I developed a reliable kick serve with my POG mid (not huge). It was basically a tool to get me to the net. I served-and-volleyed on every serve, first and second. This was my most effective strategy since my fh was so weak. I had an eastern fh grip for my forehand volley then. I was good at closing on high balls, but not so good at low volleys.

I was JV my freshman year. My sophomore year, I qualified for district in singles. Junior year, went to state in doubles.

I switched to Wilson Profile 2.7 OS before my senior year, as this racquet made my S&V style more effective. Played 1 adult NTRP tournament that year and won it (4.5). Finished my first year of USTA 18s (the only year I played enough to get a ranking) as the 22nd ranked junior in the PNW. Placed 3rd in state in doubles my senior year. I also forced myself to switch to a conti fh volley grip, which was tough, but would play dividends later.

Phase II - The physical prime years:

In my early 20s, my serve with the Profile 2.7 OS (strung at 78 lbs with Problend) developed into a huge weapon. My freshman year at Stanford, I started ranked #18 on the non-varsity ladder at Stanford. Challenge my way up to #2. The guy I beat for the #2 slot was allowed to practice with the varsity. But the coaches didn’t think my game was worthy – probably had something to do with my ugly forehand. By age 20, I was serving harder than any of the guys on the Stanford team (which won the national team title twice in the early 90s). The coaches and players marveled at my ridiculous pop attained via an insane jump serve motion (landing 6 feet inside the baseline) as if I was a Ripley’s Believe-it-or-not oddity. Coach Lele Forood called me Karsten Braasch when she walked by. Alex O’Brien called me Edberg. They thought it was funny that someone could serve that hard with such an unconventional motion. I have to give credit to coach Frank Brennan for fixing a major flaw in my forehand, which would pay off years later.

I coached the Adidas tennis camp at Stanford the summer of ’93. I had no trouble beating 14-year-olds ranked in the top hundred because they could not get my serve back.

I played sporadically in my early 20s. My big jump serve stayed big enough for me to do well in both of the tournaments I played at age 24, taking home a $40 check for placing 2nd in the ’94 Gig Harbor Open. Next tournament I entered was 3 years later - finished runner-up in a 5.0 tourney, beating a couple of seeds along the way, after only practicing for 3 weeks prior.

Phase III – Evolution into a Complete Player

At age 29, re-joined the indoor tennis club I had grew up around, and started stopping by to hit serves or play pick-up singles every day after work.

I had switched from the Profile 2.7 OS, to the Prostaff 4.7 Stretch OS. This tweener allowed my to shape my groundies more and learn how to make better use of spins. I taught myself the “racquet drop yank”, which allowed me to hit my serve just as big as before, but with less jump.

I had just as much confidence in my serve, only now I was getting more reps on my groundies too. I focused on my footwork and developed my forehand into a reliable shot (not a weapon, but a solid 4.5 level shot good enough to hang with good players). My 2hb developed into a pro-caliber major weapon. I could really do some damage with it.

I developed more of an all-court style – I still S&V’d against most players, but sometimes I’d mix it up to keep the returner honest. I was still aggressive in looking for opportunities to come to the net. Since my service games were so strong, I could afford to play defensive tennis and frustrate my opponent with safe counterpunching tennis on return games.

I played USTA 5.0 League that year, and went undefeated in singles. Won prize money twice, placing 2nd in the mixed at the Seattle City Championships, and placing 2nd in the Federal Way men’s doubles (partnering with a 4.5 junior as a favor to his coach).

I was the strongest player among the members of the club, so the head pro invited me to help out as a hitting partner for the advanced junior class twice a week. His juniors got to hit with me, and I got to hit with them for free, so it was a good deal for me. One of those juniors was pretty good, had a pro-caliber forehand, and ended up winning the WA state high school singles title 3 years in a row. I could still handle him his sophomore year since my serve and 2hb gave me enough edge, but after that, I took a year off from tennis to finish my PhD, and he passed me by for good.

Phase IV – The Racquet Geek Years

My serve atrophied from lack of practice over the past 10 years. It soon became the weakest part of my game since it was so erratic. I became a double fault machine.

However, the gradual learning process from experimenting with different weightings eventually led me to the present state. My equipment today is clearly superior to the stock frames I played with in my youth. Since my racquets are much heavier and (usually) perfectly tuned to my swings, my confidence in my baseline game is higher now than it was even during my peak competitive level years. My forehand (with tuned heavy frame) is lightyears better (strong eastern grip). I can hold my own from the baseline with 5.0 players and it’s harder for them to pick on my forehand now (unless I show up with my racquet not quite tuned). Unfortunately, I have to hold my own from the baseline, because my serve is not good enough anymore to serve and volley regularly and win consistently that way against 5.0s.

My heavy techno-racquet also makes me a better all-around volleyer than I used to be.

For competition, I consider myself a mixed specialist these days. I don’t spend enough time on the court to feel confident for league singles (injury risk too high, and I hate losing to players that I would kill if I had more time to practice), but my tuned racquets make me a force for doubles.

My game fits well with mixed doubles, since I can hold serve easier even when I have an off day, and my best skill these days is my ability to take over a doubles match when I’m the strongest player on the court. It allows me to use my speed and play the ¾ court game without being as rough on my body as singles – I love singles too, but singles is a young dude’s game. I have a 4.5 rating for league – I’ve managed to get hurt enough and practice little enough to keep from getting bumped up to 5.0. Playing mostly mixed also helps preserve my rating.

My singles style now:

Heavy spin serve if feeling good, but only come in behind it if it’s giving my opponent trouble. Just loop in the serve if feeling rusty. I use a lot of counterpunch style from the baseline. Wait for the short ball, then crush a down-the-line 2hb approach and follow it in. Or sometimes I draw my opponent to the net and then rip the pass. I use a lot of low moonballs on both sides if my opponent lets me, and sometimes I use a firm slice forehand on shoulder-ht balls if my opponent doesn’t like low balls on one of his wings. I like to mix up pace and spins a lot. My current style is similar to Andy Murray’s style.

Cool, so if you had time enough to practice and compete, I kind of imagine you would want to play a Todd Martin style of game?

J

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If I had unlimited time to practice, I'd probably favor a Rafter/Edberg approach on service games. Being only 5'11", the flat serve to the corner was never was my favorite. I prefer the heavy spinner that's hard enough to overpower. I loved the way Rafter destroyed Chang at the 97 US Open with only a slice forehand.

On return games, I'd probably still favor an Andy Murray style (mixing up the spins and rely on athleticism).

But yes, there have been times when I've also identified with players like Fish, Martin, & Wheaton just because their strengths were similar to my strengths in the past. Well, maybe not Martin - that guy looks stiff.

I didn't want to derail another thread, so I figured I would ask in your own.

Is there a reason you prefer 18g Kevlar?

J

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Honestly, there's not a lot of difference between 18g, 17g, and 16g in the way they play.

The most noticeable difference for me is the weight. A half-bed of 18g kevlar only weighs about 5 grams, while a half-bed of 16g weighs about 7g. To match the same swing dynamics, I need to add 2g at the 3-&-9 spot to make the frame strung with 18g mains swing like the one with 16g. Mass at 3-&-9 is a little more "efficient" than weight even distributed throughout the stringbed for adding power, spin, and stability. So that's a minor advantage for the thinner gauge. If I skip this mass matching step, then the thinner kevlar will feel tighter and harsher than the thicker one, but that's misleading. When I mass match, they feel similar.

When I was stringing my OS frames at 70+ lbs, I didn't have the option of using thinner gauges, because they would snap in a few hours. But at the lower tensions I've been using with slippery crosses in smaller headsize frames lately, the durability of the kevlar is no longer the limiting factor in stringbed life.

For other strings like poly (or even syn gut, but to a lesser extent), where tension stability limits the stringbed life, I prefer thicker gauges, which hold tension better than thinner ones. I just ordered a reel of Monogut ZX natural in 16g, since I'm liking my current setup in my Blade so much. As an aside, I suspect that the reason your frames were cracking with your high-tension kevlar/poly hybrid is that the kevlar holds tension so much better than the poly - within a few hours of hitting, the frame will squash a lot with that setup, and the more it squashes, the the more it stretches the poly, which in turn allows it to squash more - a destructive death spiral for your frames. You might as well of put them in a vise.